Inequality dynamics in the workplace among microbiologists and infectious disease specialists: a qualitative study in five European countries.

OBJECTIVE: To explore the social, cultural, psychological and organizational factors associated with inequality in the workplace among clinical microbiologists (CM) and infectious disease (ID) specialists in European hospitals. METHODS: We analysed data from 52 interviews and five focus groups involving 82 CM/ID specialists selected from university, research or community hospitals in five countries, one each in Northern, Western, Eastern, Southeastern and Southwestern Europe. The 80 hours of recordings were transcribed, and the anonymous database coding process was cross-checked iteratively by six researchers. RESULTS: Inequality affects all the institutions in all the countries we looked at, denying or reducing access to professional assets with intensity and form that vary largely according to the cultural and organizational context. Discrimination is generally not explicit and uses disrespectful microbehaviours that are hard to respond to when they occur. Inequality affected also loans, distribution of research funds and gender and country representation in boards and conference faculty. Parenthood has a major impact on women's careers, as women are still mainly responsible for family care. Responses to discrimination range from reactive to surrender strategies. CONCLUSIONS: Our study offers an effective model for diagnosing discriminatory behaviours in a medical professional setting. Knowledge of inequality's drivers could help national ID/CM societies in collaboration with major European stakeholders to further reduce such discrimination. The effect of discrimination on the quality of healthcare in Europe needs further exploration.

Primary resistance to integrase strand-transfer inhibitors in Europe.

OBJECTIVES: The objective of this study was to define the natural genotypic variation of the HIV-1 integrase gene across Europe for epidemiological surveillance of integrase strand-transfer inhibitor (InSTI) resistance. METHODS: This was a multicentre, cross-sectional study within the European SPREAD HIV resistance surveillance programme. A representative set of 300 samples was selected from 1950 naive HIV-positive subjects newly diagnosed in 2006-07. The prevalence of InSTI resistance was evaluated using quality-controlled baseline population sequencing of integrase. Signature raltegravir, elvitegravir and dolutegravir resistance mutations were defined according to the IAS-USA 2014 list. In addition, all integrase substitutions relative to HXB2 were identified, including those with a Stanford HIVdb score ≥ 10 to at least one InSTI. To rule out circulation of minority InSTI-resistant HIV, 65 samples were selected for 454 integrase sequencing. RESULTS: For the population sequencing analysis, 278 samples were retrieved and successfully analysed. No signature resistance mutations to any of the InSTIs were detected. Eleven (4%) subjects had mutations at resistance-associated positions with an HIVdb score ≥ 10. Of the 56 samples successfully analysed with 454 sequencing, no InSTI signature mutations were detected, whereas integrase substitutions with an HIVdb score ≥ 10 were found in 8 (14.3%) individuals. CONCLUSIONS: No signature InSTI-resistant variants were circulating in Europe before the introduction of InSTIs. However, polymorphisms contributing to InSTI resistance were not rare. As InSTI use becomes more widespread, continuous surveillance of primary InSTI resistance is warranted. These data will be key to modelling the kinetics of InSTI resistance transmission in Europe in the coming years.

Epidemiology of hepatitis D in patients infected with hepatitis B virus in bucharest: a cross-sectional study.

Epidemiological analyses indicate a decreasing level of hepatitis D (HDV) infections in most developed countries during the last 15 years. Romania, however, is one of the European countries that still has high morbidity from HDV; this study was performed in order to estimate the HDV prevalence in the Bucharest area. Three thousand four hundred sixty-one hepatitis B (HBV) infected patients were invited to participate and 1,094 were recruited. Serum anti-HDV IgG was detected in 223 patients indicating a hepatitis D seroprevalence of 20.4% (95% CI = 18.1-22.9) in patients chronically infected with HBV, less than that seen in previous studies. Seroprevalence was not gender related, but patients over 40 years were more likely to have anti-HDV antibodies, RR = 1.9 (1.2; 3.0). Detectable hepatitis D viraemia was found in 67.7% of the patients who were positive for anti-HDV. The HDV genotype was characterized for 40 isolates; all were very similar and belonged to genotype 1. Serum HBV-DNA was detectable less frequently in patients positive for anti-HDV than in patients infected with HBV alone: 68.5% versus 89.3%, OR 3.9 (1.7; 10.0), but the extent of this HDV replicative dominance varies with the sensitivity of the HBV-DNA detection. 19.3% of the subjects who tested positive for anti-HDV IgG had a HBV-DNA level higher than four logs. This high prevalence prompts the need for better HBV vaccination coverage and measures to prevent super infection with HDV in patients infected with HBV.

Detection of Mycobacterium tuberculosis resistance mutations to rifampin and isoniazid by real-time PCR.

OBJECTIVE: The objective of our study was to evaluate the use of a real-time polymerase chain reaction (PCR)-based technique for the prediction of phenotypic resistance of Mycobacterium tuberculosis. MATERIALS AND METHODS: We tested 67 M tuberculosis strains (26 drug resistant and 41 drug susceptible) using a method recommended for the LightCycler platform. The susceptibility testing was performed by the absolute concentration method. For rifampin resistance, two regions of the rpoB gene were targeted, while for identification of isoniazid resistance, we searched for mutations in katG and inhA genes. RESULTS: The sensitivity and specificity of this method for rapid detection of mutations for isoniazid resistance were 96% (95% CI: 88% to 100%) and 95% (95% CI: 89% to 100%), respectively. For detection of rifampin resistance, the sensitivity and specificity were 92% (95% CI: 81% to 100%) and 74% (95% CI: 61% to 87%), respectively. The main isoniazid resistance mechanism identified in our isolates is related to changes in the katG gene that encodes catalase. We found that for rifampin resistance the concordance between the predicted and observed phenotype was less than satisfactory. CONCLUSIONS: Using this method, the best accuracy for genotyping compared with phenotypic resistance testing was obtained for detecting isoniazid resistance mutations. Although real-time PCR assay may be a valuable diagnostic tool, it is not yet completely satisfactory for detection of drug resistance mutations in M tuberculosis.

Preliminary data on the involvement of B, C and D hepatitis viruses in the etiopathogenesis of chronic lymphoproliferative syndromes in Romania.

UNLABELLED: THE AIMS OF THE STUDY: Evaluation of the prevalence of HBV, HCV, HDV infection in patients with chronic lymphoproliferative diseases (CL), identification of the most involved viral genotypes, correlation between viremia dynamics and CL evolution, detection of molecular mechanisms implicated in CL pathogenesis, identification of lymphocytic receptors for viral antigens and biologic markers for early diagnosis of CL. METHODS: We present preliminary results of the first year of our research grant. This is a prospective, analytic, observational study in patients diagnosed with CL and HBV, HCV, HDV chronic infection. We included the following forms of CL: non-Hodgkin malignant lymphoma (NHL), Hodgkin lymphoma (HL) and chronic lymphocytic leukemia (CLL). We used the following commercial test kits: HCV RNA Real time PCR on a COBAS TaqMan (Roche Diagnostics) analyzer with 28 to 140.000.000 UI/ml detection range for HCV viremia, HBV DNA Real time PCR on a COBAS TaqMan (Roche Diagnostics) analyzer with 6 to 110.000.000 UI/ml detection range for HBV and the Roboscreen-RoboGene AJ kit with 10-10.000.000 replica/ml detection range for HDV. RESULTS: We have included 20 patients with CL and chronic hepatitis infection so far. Median age of the patients was 61 years. The identified CL forms were: B cell NHL (15 cases), T cell NHL (1 case), CLL (3 cases), Hodgkin lymphoma (1 case), equally distributed in aggressive and indolent forms of CL. HCV infection was diagnosed in 10 patients with CL, HBV infection was found in 10 patients with CL, 3 of them having co-infection HBV + HDV. In 4 patients with HBV infection viremia was over 20.000 IU/ml and the pattern of the CL was the aggressive form of the disease. The feature of the co-infection HBV + HDV was the predominance of indolent forms of CL. Among patients with HCV infection, only 3 cases were detected with viremia over 600.000 IU/ml and CL was represented by aggressive forms of the disease. We also have immunohistochemical data available in 19 cases, which seem to confirm the role of hepatitis viruses in lymphoproliferative disease etiopathogenesis. CONCLUSIONS: We ascertained an almost equally represented prevalence of HCV and HBV infection in patients with CL. The levels of HBV, HCV and HDV viremia were low in most of the cases. The most frequent form of CL was B cell NHL. We found an equal distribution between indolent and aggressive forms of NHL associated to hepatitis virus infection.

Impact of highly active antiretroviral therapy on cytomegalovirus viraemia in the absence of specific anti-cytomegalovirus therapy.

OBJECTIVES: (1) to evaluate the effect of HAART on CMV viraemia in co-infected patients, in the absence of specific anti-CMV therapy; (2) to compare 2 molecular biology techniques for the detection and quantification of CMV-DNA in these patients. METHODS: We present the preliminary data of an ongoing prospective research grant on newly diagnosed HIV seropositives, in a tertiary care hospital, during June 2006- June 2008. Clinical, virological (HIV and CMV viraemia) and immunological (CD4) screening was performed every 3 months. The CMV viraemia was performed by RoboGene Human Cytomegalovirus Quantification kit (aj Roboscreen). We retested all undetectable CMV viremia found in patients with CD4 <50/mmc, by CMV PCR kit (Qiagen Diagnostics). Both PCR reactions were performed on ABI Prism 7000 (Applied Biosystems). RESULTS: Up to date, our study has included 105 HIV-infected subjects, who were seropositive for anti-CMV IgG antibodies. Average follow-up was 18 months. CMV viraemia was found detectable in 21 cases at first visit and in other 5 at the second visit. 22 cases had CD4 <50/mmc, among which 14 had undetectable CMV viraemia. The results of both molecular biology techniques were widely the same. HAART was prescribed to 86% of the patients; all the patients having detectable CMV viraemia received HAART, but not any specific anti-CMV therapy. Under HAART, all the detectable CMV loads which were retested in time became undetectable at next visits, after a median of 16.5 weeks from the introduction of therapy. CONCLUSIONS: CMV viraemia detection was useful in early diagnosis of asymptomatic CMV infection. As opposed to transplant cases, molecular biology techniques for the detection and quantification of CMV-DNA in HIV-patients have not been standardized yet. In our study, the two kits RoboGene Human Cytomegalovirus (HCMV) Quantification kit (aj Roboscreen) and CMV PCR kit (Qiagen Diagnostics) were comparable. HAART made the reduction of CMV viral load, without any specific anti-CMV therapy. As in the case of other opportunistic infections, undetectable natural history of CMV infection seemed to have been improved by controlling HIV infection.

Evolution of the Sabin type 1 poliovirus in humans: characterization of strains isolated from patients with vaccine-associated paralytic poliomyelitis.

Attenuated strains of the Sabin oral poliovirus vaccine replicate in the human gut and in rare cases cause vaccine-associated paralytic poliomyelitis (VAPP). Reversion of vaccine strains toward a pathogenic phenotype is probably one of the main causes of VAPP, a disease most frequently associated with type 3 and type 2 strains and more rarely with the type 1 (Sabin 1) strain. To identify the determinants and mechanisms of safety versus pathogenicity of the Sabin 1 strain, we characterized the genetic and phenotypic changes in six Sabin 1-derived viruses isolated from immunocompetent patients with VAPP. The genomes of these strains carried either few or numerous mutations from the original Sabin 1 genome. As assessed in transgenic mice carrying the human poliovirus receptor (PVR-Tg mice), all but one strain had lost the attenuated phenotype. Four strains presented only a moderate neurovirulent phenotype, probably due at least in part to reversions to the wild-type genotype, which were detected in the 5' noncoding region of the genome. The reversions found in most strains at nucleotide position 480, are known to be associated with an increase in neurovirulence. The construction and characterization of Sabin 1 mutants implicated a reversion at position 189, found in one strain, in the phenotypic change. The presence of 71 mutations in one neurovirulent strain suggests that a vaccine-derived strain can survive for a long time in humans. Surprisingly, none of the strains analyzed were as neurovirulent to PVR-Tg mice as was the wild-type parent of Sabin 1 (Mahoney) or a previously identified neurovirulent Sabin 1 mutant selected at a high temperature in cultured cells. Thus, in the human gut, the Sabin 1 strain does not necessarily evolve toward the genetic characteristics and high neuropathogenicity of its wild-type parent.

[An evaluation of the identification technics with IS6110 and Mt308 used as molecular markers for Mycobacterium tuberculosis strains isolated in Romania]. / Evaluarea tehnicilor de identificare a IS6110 si Mt308 utilizate ca markeri moleculari pentru tulpinile de Mycobacterium tuberculosis izolate în România.

During the past years, new diagnostic technologies based on DNA methods including PCR, were developed in the aid of tuberculosis control. Among several DNA sequences, an insertion sequence IS6110, found to be specific to mycobacteria belonging to M. tuberculosis complex were used. However, recent studies showed the absence of this IS6110 in 3-4% of M. tuberculosis strains isolated from patients of Vietnamese origin. In order to evaluate the frequency of IS6110 among a series of strains isolated in Romania, we have performed the PCR technique for amplification of 2 DNA specific regions of M. tuberculosis complex. The sequences of primers were as shown before (Guesdon et al., 1990). For this study, 219 strains have been isolated from tuberculous patients, in "Marius Nasta" Institute of Bucharest, Romania. We have shown that genomic DNA from 3.6% of 219 strains evaluated in our study do not contain the IS6110 sequence and could determine some identification problems when this molecular sequence is targeted.

The replacement of water with deuterium oxide significantly improves the thermal stability of the oral poliovirus vaccine.

The poliomyelitis eradication programme relies largely on the massive administration of the oral poliovirus vaccine (OPV). The major difficulty in assuring good vaccine coverage, especially in hot climates, is the thermostability of the vaccine. Several attempts have been made to stabilize the OPV with limited benefits. In this report, we describe a heavy water based stabilization procedure, which has been shown to increase the thermostability of the vaccine, notably at temperatures which are commonly encountered during usual transportation in conditions of cold chain failure. Safety considerations regarding the human use of heavy water containing bioproducts are discussed.

Antibiotics and bacterial resistance. A few elements of genetic basis for this relationship.

In the preantibiotic era, many people died of bacterial infections caused by such pathogens as Staphylococcus aureus and Streptococcus pyogenes, Streptococcus pneumoniae and Mycobacterium tuberculosis. Antibiotics have reduced the mortality from infectious diseases but not the prevalence of these diseases. It was not long after the clinical introduction of the first antibiotics in the 1950s that the first reports of bacterial resistance began to appear. Use, and often abuse or misuse, of antimicrobial agents has encouraged the evolution of bacteria toward resistance, resulting often in therapeutic failure. In the beginning, new antibiotics have always appeared in plenty of time to provide new cures for diseases caused by resistant bacterial pathogens. Also, some clinically important groups of bacteria showed no signs of major increases in resistance. For example, S. pneumoniae strains remained susceptible to penicillin long after other bacteria had become resistant to it. Recent developments of bacteria resistance to antibiotics are indeed disquieting.

Point mutations involved in the attenuation/neurovirulence alternation in type 1 and 2 oral polio vaccine strains detected by site-specific polymerase chain reaction.

One of the problems raised by the use of the attenuated oral poliovirus vaccine (OPV) Sabin strains is the genetic instability of the attenuated phenotype upon multiplication in vivo. Nucleotide sites critical for attenuation were identified for each of the three poliovirus serotypes. One important position lies in the 5' non-coding region of the genome of each of the three OPV strains, at nucleotide 480 in type 1, 481 in type 2 and 472 in type 3. Point mutations at these positions were usually selected upon multiplication in vivo as substitutions of the vaccine-type residue. The reversion was found to correlate with an increased degree of neurovirulence. To screen easily for this mutation in a great number of strains, we developed a site-specific polymerase chain reaction method based on the property of the Taq polymerase to elongate only primers with a perfect homology at the 3' extremity. We screened for this mutation in five type 1 and nine type 2 polio vaccine-derived strains isolated from vaccine-associated paralytic poliomyelitis (VAPP) cases and in 16 such strains isolated from healthy vaccinees. All 14 strains isolated from VAPP presented the reversion. Of the eight pairs of type 1 isolates from healthy vaccinees, four presented the reversion 3 days after vaccine administration and all but one at 7 days postvaccination. These results support the involvement of the 5' non-coding specific nucleotide sites in the reversion to neurovirulence of attenuated polio vaccine strains upon multiplication in the human gut.(ABSTRACT TRUNCATED AT 250 WORDS)

Polioviruses with natural recombinant genomes isolated from vaccine-associated paralytic poliomyelitis.

To determine how oral poliovirus vaccine (Sabin) strains evolve during replication in humans and to confirm the etiology of vaccine-associated paralytic poliomyelitis (VAPP), we examined 70 vaccine-derived strains isolated from VAPP cases. Two distant sequences of the poliovirus genome were targeted for a double restriction fragment length polymorphism assay (RFLP) of reverse-transcribed genomic segments amplified by PCR, an extension of the method that we described previously (Balanant et al., 1991). One (RFLP-1) was a 480-long nucleotide sequence coding for the N-terminal part of the VP1 capsid polypeptide, situated in the 5' third of the viral genome (nucleotides 2401-2880). The other (RFLP-3D1) was a 291-long nucleotide sequence coding for a part of the viral polymerase, situated near the 3' end of the genome (nucleotides 6086-6376). Strain-specific restriction profiles could be generated for different field isolates by using three restriction enzymes in each case: HaeIII, DdeI, and HpaII for RFLP-1 and HaeIII, DdeI and RsaI for RFLP-3D1. With few exceptions, the vaccine-specific RFLP profiles were found to be conserved in both regions during replication of these viruses in humans. Thus, RFLP could be used as a marker so as to identify the origin of viral isolates at both ends of their genome. Whether viral isolates were vaccine-derived was determined by using strain-specific monoclonal antibodies and RFLP-1. Among the 70 isolates, 21 of the 43 type 2 strains and 15 of the 22 type 3 strains had a recombinant genome. None of the 5 type 1 Sabin-derived isolates was found to be recombinant. Both intertypic vaccine/vaccine and vaccine/non-vaccine recombinants were detected. Partial nucleotide sequencing confirmed the RFLP results in all cases that were investigated. In one case, it was possible to predict the recombination junction site from the restriction profiles. This site was more precisely localized by sequencing. The C6203 > U nucleotide substitution, which is suspected to contribute to the reversion toward neurovirulence of the attenuated Sabin 1 strain, was detected in almost all the recombinant genomes containing Sabin 1-specific sequences at the 3' extremity. This mutation was detected by identification of the modified RsaI profile in the RFLP-3D1. The results presented in this paper suggest that recombination, alone or together with mutation, might be one of the mechanisms of the reversion toward neurovirulence of attenuated vaccine strains and of the natural evolution of poliovirus.

Genomic modifications in naturally occurring neurovirulent revertants of Sabin 1 polioviruses.

Five type 1 Sabin-like poliovirus strains were isolated from paralytic cases of poliomyelitis. Their Sabin origin was confirmed by antigenic analysis with monoclonal antibodies and restriction fragment length polymorphism (RFLP) assay. Several nucleotide positions known to play a role in the reversion towards neurovirulence were examined: viz 480, 2741, 6203, 7441. Analysis was performed by enzymatic restriction and partial sequencing of PCR-amplified genomic segments. All the strains bore the reversion G > A at residue 480; in four of the five viruses, only this reversion was found. The fifth strain presented four additional reversions and several new mutations. These results indicate that, during multiplication in the human gut, Sabin 1 poliovirus carrying one or several mutations related to reversion towards neurovirulence can be selected.